Update eslint-plugin-flowtype to version 2.21.0 🚀

[greenkeeperio-bot]

Hello lovely humans,

eslint-plugin-flowtype just published its new version 2.21.0.

State	Update 🚀
Dependency	eslint-plugin-flowtype
New version	2.21.0
Type	devDependency

This version is not covered by your current version range.

Without accepting this pull request your project will work just like it did before. There might be a bunch of new features, fixes and perf improvements that the maintainers worked on for you though.

I recommend you look into these changes and try to get onto the latest version of eslint-plugin-flowtype.
Given that you have a decent test suite, a passing build is a strong indicator that you can take advantage of these changes by merging the proposed change into your project. Otherwise this branch is a great starting point for you to work on the update.

Do you have any ideas how I could improve these pull requests? Did I report anything you think isn’t right?
Are you unsure about how things are supposed to work?

There is a collection of frequently asked questions and while I’m just a bot, there is a group of people who are happy to teach me new things. Let them know.

Good luck with your project ✨

You rock!

🌴

---

The new version differs by 4 commits .

• b22a29d chore: release 2.21.0
• a297159 docs: update documentation
• 715a389 Merge pull request #138 from gajus/variance
• 4a7f87f feat: Add variance support to spaceBeforeTypeColon & spaceAfterTypeColon

See the full diff.

---

This pull request was created by greenkeeper.io.

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[codecov-io]

Current coverage is 88.26% (diff: 100%)

Merging #479 into master will not change coverage

@@             master       #479   diff @@
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  Files           170        170          
  Lines          1824       1824          
  Methods           0          0          
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  Branches          0          0          
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  Hits           1610       1610          
  Misses          214        214          
  Partials          0          0          

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